The present invention relates to a latch for locking a door in a closed position, and in particular to a motorized oven door securing latch used to preclude access to a self-cleaning domestic range oven undergoing a high temperature pyrolytic cleaning cycle.
Motorized self-cleaning oven door latches are well known in the art as represented by U.S. Pat. No. 3,859,979 to Gilliom and U.S. Pat. No. Re. 27,545 to Guy. Latches of the type illustrated by these patents include a rotary motor mounted at a rearward portion of the range body above the oven chamber and a reciprocating latch hook at a forward portion of the range body, the latch hook being engageable with a keeper fixed to the closed oven door.
To effect reciprocating movement of the latch into and out of engagement with the keeper, a translationally movable, longitudinal member is provided between the motor means and the latch hook.
In U.S. Pat. No. 3,859,979, the longitudinal member is a latching rod motor driven back and forth along its axis by an eccentric mount in reciprocating fashion to and away from the oven door while being cocked from side to side as it moves with a cam rivet to effect door latching and unlatching. In U.S. Pat. No. Re. 27,545, an eccentric drive arrangement moves a latch rod back and forth along its axis in reciprocating fashion to effect latching and unlatching of a latch member with an associated oven door.
In both of the above-noted prior art devices, it is necessary to convert the rotational movement of an accompanying rotary drive motor into translational motion to effect reciprocating movement of the latch rods. The resultant mechanisms are necessarily complex and, as a result of their complexity, are high in cost. Since the domestic appliance business is extremely cost competitive, and since long-term durability is a major factor in appliance design, there is great need for a less costly and simpler motorized latch mechanism to replace mechanisms of the type illustrated by the above-noted patents.
Further, the user control of such motorized latches should be simple, straightforward, and of a fail-safe nature to provide for a hazard-free oven cleaning operation. Multiple control manipulations performed by the user in a complex sequence to effect door latching should be avoided without risking safety.
It is the purpose of the present invention to meet all the criteria noted above with regard to a more ideal motorized oven door latch and control of the same.